Subtract 81/40 from 20/12
1st number: 1 8/12, 2nd number: 2 1/40
20/12 - 81/40 is -43/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 12 × 10 = 120,
20/12 = 20 × 10/12 × 10 = 200/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
81/40 = 81 × 3/40 × 3 = 243/120 - Subtract the two like fractions:
200/120 - 243/120 = 200 - 243/120 = -43/120
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